This invention relates to instruments and methods for performing laparoscopic surgery, particularly to instruments for introducing a suture to the inside of the body of a patient for use in ligation or retraction and methods for use thereof.
In performing laparoscopic surgery it is often desirable to use a suture to tie off, that is, ligate, a conduit such as a vessel or duct inside the body of a patient or to retract a structure inside the body of the patient. Ligation is accomplished by looping the suture around the vessel or duct, tying a slip knot with one end of the suture around the other end of the suture and cinching the knot down on the vessel or duct to close it off. Similarly, to retract a structure inside the body, the suture is looped around the structure and the ends of the suture are used to pull on the structure. Ordinarily, the suture is introduced through a cannula by attaching the suture to a needle and feeding the needle through the cannula into the body of the patient. Another surgical tool, such as a grasping forceps, introduced through another port in the body is then used to manipulate the needle inside the body of the patient. The needle is forced through the wall of the abdomen, from the inside out. Where ligation is the object, the end of the suture extending through the abdomen wall is cut inside the body of the patient, tied around the end of the suture extending out the cannula and cinched down on the duct or vessel. Where retraction is the object, the end of the suture extending out the cannula and the end of the suture extending through the wall of the abdomen are grasped and pulled to retract structure inside the body.
One problem with existing instruments and methods for ligation and retraction is that it is difficult to manipulate the needle inside the body of a person without puncturing organs or other tissue inside the body, which usually causes undesirable and dangerous complications. Another problem is that it is difficult to force the needle through the wall of the abdomen, which comprises the peritoneum, muscle, a layer of fat and the epidermis, from the inside out. A further problem is that existing instruments employ a cannula that opens about a 5 mm wound in the abdomen and the needle opens yet a further, though much smaller, wound; these wounds slow patient recovery and increase the chance that complications may occur.
Therefore, it would be desirable to have an improved instrument and method for introducing a suture to the inside of the body of a patient without the degree of trauma and difficulty experienced with conventional means for doing so.